Variable diameter tube for use in a vasal inserter for performing hemodynamics researches and related operations and method for making said tube

1. A variable diameter tube, comprising:

a first material layer comprising a C-shaped cross-section, the first material layer comprising polyether ether ketone and only one longitudinal cut; and

a second material layer comprising polyurethane, wherein the second material layer is coupled to the first material layer along an outside surface of the first material layer such that the second material layer is disposed around the first material layer, wherein the second material layer is not coupled to lateral surfaces of the longitudinal cut, the variable diameter tube configured to transition between a rest condition, wherein the variable diameter tube has a rest diameter, and an enlarged diameter condition, wherein the variable diameter tube has an enlarged diameter;

wherein the second material layer is flexible such that a displacement between the lateral surfaces of the longitudinal cut increases as an object having a diameter that is greater than the rest diameter of the variable diameter tube is inserted into the variable diameter tube,

wherein the second material layer is more resilient than the first material layer such that transition of the variable diameter tube from the rest condition to the enlarged diameter condition increases the displacement between the lateral surfaces of the longitudinal cut and stretches at least a portion of the second material layer; and

wherein the second material layer defines a folded flap, the folded flap extending inward between the lateral sides of the longitudinal cut when the variable diameter tube is in the rest condition.

2. The variable diameter tube of claim 1 , wherein the first material layer further comprises carbon fiber reinforcing components.

3. The variable diameter tube of claim 1 , wherein the second material layer has a shape memory in that it returns to the rest diameter when unconstrained.

4. The variable diameter tube of claim 3 , wherein the rest diameter is about 3.2 mm.

5. The variable diameter tube of claim 1 , further comprising a lubricating material disposed on the first material layer.

6. The variable diameter tube of claim 1 , wherein the first material layer is glued to the second material layer.

7. The variable diameter tube of claim 1 , wherein the diameter of the variable diameter tube is variable by at least one millimeter between the rest condition and the enlarged diameter condition.

8. A variable diameter tube, comprising:

a first material layer comprising a C-shaped cross-section, the first material layer comprising polyether ether ketone and only one longitudinal cut; and

a second material layer comprising polyurethane, wherein the second material layer is coupled to the first material layer along an outside surface of the first material layer, wherein the second material layer is not coupled to lateral surfaces of the longitudinal cut, the variable diameter tube configured to transition between a rest condition and an enlarged diameter condition;

wherein the second material is flexible such that a displacement between the lateral surfaces of the longitudinal cut increases as an object having a diameter that is greater than a rest diameter of the variable diameter tube is inserted into the variable diameter tube,

wherein the second material is more resilient than the first material such that when the variable diameter tube transitions from the rest condition to the enlarged diameter condition the displacement between lateral surfaces of the longitudinal cut increases and at least a portion of the second material stretches;

wherein the second material is disposed around the first material; and

wherein the second material defines a U-shaped folded flap that extends radially inward between the lateral surfaces of the longitudinal cut when the variable diameter tube is in the rest condition such that the displacement between the lateral surfaces of the longitudinal cut is completely occupied by a portion of the U-shaped folded flap of the second material layer.

9. The variable diameter tube of claim 8 , wherein the diameter of the variable diameter tube is variable by at least one millimeter between the rest condition and the enlarged diameter condition.

10. The variable diameter tube of claim 1 , wherein the folded flap is U-shaped.